Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Loss (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (76,766)	$ (39,453)	$ (50,375)	$ (53,918)
Foreign currency translation adjustments	(31,461)	13,874	16,765
Net unrecognized losses related to defined benefit pension plan (see Note 17)	(9,787)	(4,065)	(13,222)
Amounts reclassified from accumulated other comprehensive loss	3,935	1,113	0
Other comprehensive (loss) income	(37,313)	10,922	3,543
Accumulated Translation Adjustment [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(33,223)	(1,352)	(16,084)	(34,012)
Foreign currency translation adjustments	(33,929)	14,732	17,928
Net unrecognized losses related to defined benefit pension plan (see Note 17)	0	0	0
Amounts reclassified from accumulated other comprehensive loss	2,058	0	0
Other comprehensive (loss) income	(31,871)	14,732	17,928
Accumulated Defined Benefit Plans Adjustment [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(43,543)	(38,101)	(34,291)	(19,906)
Foreign currency translation adjustments	2,468	(858)	(1,163)
Net unrecognized losses related to defined benefit pension plan (see Note 17)	(9,787)	(4,065)	(13,222)
Amounts reclassified from accumulated other comprehensive loss	1,877	1,113	0
Other comprehensive (loss) income	$ (5,442)	$ (3,810)	$ (14,385)